What's Next

I started this subject in another Forum but thought it might get more interest here.

Probably not a new idea but ...

I think that the quest for perfection in design and performance, as Mr Perry mentions in another thread, will lead to a creation that is at once magnificent and a little dull at the same time. When I watch a video of a 60+ year old couple (the Dashews) making a fruit salad while reaching at 27 knots on their 80 foot aluminum ketch making 300+ miles per day, it gives me a glimpse of things to come. And this was over ten years ago!

I got amped up on caffeine and got to thinking. Many features on a sailboat can be adjusted and modified for any given condition - switching up sails, reconfiguring sail plans, out hauls, cunninghams, back stays, boom vangs, sheets and now trimming ailerons on wings for optimal performance. Keels can be canted and ballast can be moved with water. Some masts telescope and some hulls are fitted to foils.

What hasn't changed so much is the ability of the shape of the hull to change. So far it seems to me it's one size fits all or one needs to come up with the best design for all possible points of sail or specific conditions. I think this could change.

At the Museum of Science in Los Angeles there is a kinetic sculpture made from thousands of pieces of aluminum. It's geometry expands and contracts using an electric motor. It closes to within perhaps twenty square feet and opens to ten times that size.

Could it be possible to create ribs and a spine like those on old wooden boats with a system like this made from ultra light carbon or some Nano material? Over this a Nano type skin could be fixed at certain points over this skeleton so that when the structure expands the skin would stretch and the tensile strength of the skin would increase until a hull shape is formed. Once taught, the skin would have the same or greater rigidity of a carbon hull...kind of like stretching a buckskin to make a canoe or a condom depending on which way you want to think about it. The mast would be attached to the spine and an inner water tight cabin could be shielded by this ballistic strong outer skin (like an oil tanker). The skin could be replaced periodically or as needed.

Initially, the frame would be able to morph into limited shapes based on predictable sea states and points of sail ie upwind in flat sea, surfing downwind in a heavy sea etc. maybe turning the bow up, narrowing the beam, widening the aft section, a chine or two etc. The electric motors would be governed by computers taking information from sophisticated weather, hydro dynamic and navigation systems. As these systems improve, changes in hull shape could take place more rapidly and on the fly. These changes would also take place in accordance with changes in wing shape (if that's what will be used) and trim, ballast, keels and/or foils. Of course, solar cell and wind generators and battery storage will be much improved, enough so to provide ample power. Maybe there will be one of those mini nuclear reactors on board, the ones that are being developed for home use.

In this way, I think a fully automated sailing vessel such as this may finally bring synergy between water and air, slipping atop the sea like a blade across ice. It's ability to make thousands of micro adjustments to every wave and wind shift would optimize performance more so than the best crew could ever hope to accomplish.

It sounds far fetched but drones are replacing manned fighter jets, Google is close to developing autonomous cars, nano materials are already being used, we can model any sea state and wind scenario in a computer already. Boats like the AC, Speed Dream, Hydroptere and Sail Rocket are incorporating these ideas already. The shift to foils and wings is inevitable, I think.

It also seems inevitable that many other systems will become automated. What percentage of the typical Vendee boat sail under auto pilot? AC crew talk about the dampening effect of foils, above the water, not crashing through it with walls of water pouring over the crew like V70's in the Southern Ocean. With little to no displacement from a hull, there is less done about sail changes. Wings are trimmed to counter loads. All this progression towards perfection, conquering the elements seems to be removing us from the picture or at least it is changing the description of what a sailor is. Will we become obsolete?

I romanticize the old days, rounding the horn in square rigs or boats like Suhaili, hanging on for dear life, tumbling down rogue waves... The Horn is no less a dangerous place but where it was once a place that was feared (yes I know it still is) it has now become a place of sport. Some day soon some nut will round it on a modified wind surfer or kiteboard. Carnival cruises will take retirees on joy rides in big luxurious multi hulls paying for the privilege like some do to go into space.

Picture a glorious mega yacht with great white wings hovering on foils powering at 60knts rounding the horn through monstrous seas, completely automated with two geriatrics, oblivious to the spectacle, reclining in the doghouse, eating fruit salad while watching reruns of Charmed.

What about the military applications of this? A drone in glide formation thousands of feet about the earth suddenly transforms into a stealth fighter, tucking its wings into it's underbody and diving like a hawk onto a lowly, unsuspecting F-16.

trim tabs, flaps and similar devices used on aircraft and boat hull accomplish the same thing in a lighter and more reliable way.

Flexible skins with movable support structure has been used on aircraft from the very beginning, the wright flyer used "wing warping" for flight controls, it was also tested on an F-111B in the 80's (mostly to eliminate the gaps and hinge lines to lower the radar signature). But it make the hull or fuselage heavy and complex, with lots of moving parts. The idea of swing wing aircraft for example has fallen away because the performance advantage is not enough to compensate for weight, costs and complexity (high maintenance). The future has been simple less complex design, and use better design tool to accomplish that.

I think by reducing the number of parts and making everything lighter, and keeping the costs down, is the way of the future. The real challange, like in the aircraft, is to use advnaced design tools, better CFD and materials, to make something that performes well at all speeds, with fewer moving parts. Weight and cost are the enamy, consider how much cheaper an aircraft would be if it did not have to have a complex triple slotted flap system, but if there was some way to make the wing generate high lifts at low speeds so it could still land at a reasonable speed, but not have too large a wing for cruising flight. the same is true with sailboat hulls and sails, make them weigh less and shaped so they perform well in both light winds at displacement speeds, but also controllable in high winds at planing speeds.

there was a thread about this topic about a power boat with some flexible panels to reducing pounding in chop. It can be done, but it will add weight and cost. the real question is, is there a shape that will not pound in chop, yet also come up on plan early and have lower drag at all speeds.

Thank you very much for replying. As I am not an engineer there are so many things I wouldn't consider. I work more on the concept side and let the mathematicians work out the details.

Construction costs aside as those considerations are thrown out the window at the concept stage, I understand the need for simplicity and a reduction in weight. But, aesthetically speaking and maybe there is something in the aesthetics, extraneous parts on a boat seem awkward and wrong to me, unnatural. Ten foot keels with huge bulbs on the end, trim tabs etc pose so many problems. If you are saying, the same thing can be achieved by modifying hull shape but the deterrent is weight, complexity and cost then it seems possible that, just like in all designs, these parameters will improve over time. I mean we have come a long way from old wooden square rigs, even from fiberglass production. Although I understand the concept behind Speed Dream, the low drag efficient hull, the kanting keel just looks absurd, to me.

I just feel instinctually (maybe not intellectually - I don't have the training) that when dealing with elements such as air and water and trying to pass an object through both of them at the same time, the object needs to accommodate these elements, not force past or through these elements. It needs to adjust and morph as evolution has created so many more efficient objects that change and adapt to these elements.

one other consideration too, the reason why most cruising sailboats look the way they do is becasue that is what people want to buy. There is not much of a market for recreational sailboats that look like half of an aircraft sticking out of the water, even though it may sail faster and better. It is called market acceptance. Most buyers want a sailboat to look like a sailboat. and most classes of racing outlaw anything that does not look like a sail boat.

except the few pure open classes, but boats like Speed Dream are not really practical for open water sailing.

Until they make force fields and antigravity you will be seeing technology similar to what we use today.

Bottom line is morphing technology is mostly DARPA pipe dreams and even then only for UAV's. Morphing does not scale well, the stresses and weight grow with the cube of size so it is not practical on human size vehicles.

Boats are even worse since the forces are magnitudes higher than flying.

The only viable option is foils. Boats have to displace a volume of water equal to their weight. No amount of hull optimization is going to make a huge difference in speed or efficiency. The only practical option is to get that mass out of the water.

Now that the Americas Cup boats are foiling boats I think the near future will see huge gains in foiling technology. That should lead to gains in efficiency.

"In theory there is no difference between theory and practice. In practice there is."

Petros, not really interested in market acceptance at the concept stage. Just throwing around some ideas. Don't auto makers hone down concepts into something that is marketable? If designers and engineers didn't always push the envelope, where would we be? A crazy idea could lead to something very functional. Happens all the time.

Are you saying that it is possible that one day advances in foil design will be able to lift any amount of mass out of the water? Wouldn't that take a lot of energy? Could wings ever deliver that much force to lift, say, a tanker out of the water? I suppose it's possible.

The primary problem with applying shape-changing structures and/or materials to boats - or any other transport medium - would be safety, given the necessary strength-to-weight ratio, and ignoring cost of course. If the exterior changes shape the interior is going to change also. This could inconvenience the occupants, or worse.

Thus the changes must either be small, or achieved with the boat empty. In the first case, could a sufficiently small change accommodate a change from efficient displacement hull to fast planing hull, for example? Doug would propose retracting foils as an alternative. That would be simpler, surely. Flexible hulls have already been tried and were unsuccessful as well as being too uncomfortable for human transportion.

The second case has more chance of short-term implementation and commercial success, by making possible a boat that could change, not just shape, but size, allowing convenient storage, rapid deployment for use on the water.

I felt this was likely to be done first in a canoe; what paddlers would like is a boat that actually folds into a compact form but simply unfolds, stretches, morphs or whatever to its proper shape for use on the water. There are lots of "folding" canoes out there which do not really fold - they come apart, and despite manufacturers claims it is time-consuming to convert them from one form to the other. This is evidenced by the fact that most users dismantle their boat only for storage over the Winter months, or perhaps to carry as luggage on an aircraft.

A realistically achievable folding boat would require a folding frame with hinges of a complex nature and some kind of rigidizing mechanism. The folding frame is a 3-dimensional topological problem that has not been figured out yet: primitive examples of rigidizing mechanisms already exist on canoes that dismantle but do not fold. As far as the skin is concerned, I think there are already modern fabrics that will fill the bill there. A folding boat has been implemented with a rigid skin but not in a hydrodynamically efficient form, at least as far as I know.

I was trying to design a true folding boat a few years back, with inspiration from products made by my former aerospace company to guide me. However, those products were modular, consisting of multiple identical elements connected together: solve the problem for one element and you've solved the problem for all of them. It could be done if paddlers would be content with a parallel-sided boat, which I doubt. I got close but the complex shape of the typical hull defeated me as I suspect it has defeated others.

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